A built-up sandwich panel may include a core that is sandwiched between two face sheets and resistance welded or brazed to the face sheets. A built-up sandwich panel made of titanium is light in weight and resistant to corrosion, it has higher strength than most metals, and it can survive extreme temperature environments. In addition, it may be treated for noise attenuation.
These features make titanium built-up sandwich panels desirable for aircraft structures such as jet engine nacelle inner walls.